Chair with ergonomic motion features

ABSTRACT

A chair includes a seat pan member, a movement support frame, and at least two movement support members operatively connected to the seat pan member and the movement support frame. The at least two movement support members are configured to support the seat pan member in a floating manner for dynamic movement with respect to the movement support frame in at least one degree of freedom in a horizontal seating plane.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application relies on the benefit under 35 U.S.C. § 119(e)of U.S. Provisional Patent Application Ser. No. 62/173,388, filed onJun. 10, 2015, which is incorporated herein by reference in itsentirety.

BACKGROUND

Field

The present patent application relates to chairs. In particular, thepresent patent application relates to chairs having ergonomic motionfeatures.

Description of Related Art

Chairs are generally designed to support a user in two locations, forexample, in the seat pan area and along the back. Some chairs aredesigned to provide support to the user in the lumbar region as well.The seat back (including the lumbar support) and the seat pan are thecomponents of the chair that come in contact with the user's body whenthe user is seated in the chair.

Simple padded seating, contoured padded seating and engineeredbreathable mesh seating have also been developed to provide comfort andsupport to the user. Some of the chairs also include a plethora ofadjustments that allows the user to adjust the seat to an optimalposture position. For example, ergonomic chairs can be adjusted into anoptimal position for each user.

Also, chairs are generally designed based on decades-long “ergonomic”theories. These theories usually attempted to accommodate the user instagnate (i.e., static) correct posture positions. Recently, the conceptof sitting too long in a stationary position, no matter how correct theposture position may be, has been considered to be unhealthy.

Further, there has also been an interest in non-traditional ergonomicseating within the workplace environment. These products are usuallybased on seating that is not chair based. For example, thenon-traditional ergonomic seating may include stools that pivot off abase, or are shaped like mushroom heads or saddles. Each of thenon-traditional ergonomic seating is based on some sort of observationof freedom of movement versus the stationary classic ergonomic design.Due to their unusual design or the additional problems that these typeof seating devices may create, they have not been widely adapted.

SUMMARY

In one embodiment of the present patent application, a chair isprovided. The chair includes a seat pan member; a movement supportframe; and at least two movement support members operatively connectedto the seat pan member and the movement support frame, the at least twomovement support members are configured to support the seat pan memberin a floating manner for dynamic movement with respect to the movementsupport frame in at least one degree of freedom in a horizontal seatingplane.

In another embodiment of the present patent application, a chair isprovided. The chair includes a seat base member, a seat back member, aseat base support member and a suspension assembly. The suspensionassembly is operatively connected to the seat base member and the seatbase support member and is configured to support the seat base member ina suspended manner for dynamic movement with respect to the seat basesupport member in at least one degree of freedom in a horizontal seatingplane.

In yet another embodiment of the present patent application, a chair isprovided. The chair includes a seat pan member, a seat back memberhaving a lumbar support member, a lumbar support assembly and anactuator. The lumbar support assembly is operatively connected to thelumbar support member and configured for moving the lumbar supportmember, with respect to the seat pan member and the seat back member,between a first position and a second position. When the lumbar supportmember is in the second position, the lumbar support member ispositioned forwardly, in a direction toward the seated user's lowerback, relative to the seat back member so as to enable the user to beseated forwardly on the seat pan member while being engaged with thelumbar support member. The actuator is configured to operate the lumbarsupport assembly for movement of the lumbar support member between thefirst position and the second position.

In yet another embodiment of the present patent application, a chair isprovided. The chair includes a seat pan member, and an ergonomicposition sensor arrangement operatively connected to the seat panmember. The sensor arrangement is configured to sense the position of auser seated on the seat pan member for outputting data to determine howthe user is sitting in comparison to a predetermined sitting position.

In yet another embodiment of the present patent application, a chair isprovided. The chair includes a seat pan member, an ergonomic positionsensor arrangement operatively connected to the seat pan member, and adisplay device with a processor. The sensor arrangement is configured tosense the position of a user seated on the seat pan member foroutputting data. The processor is configured to receive the data fromthe sensor arrangement, compare the received data to a predeterminedtarget sitting position, and display an indication of the comparison tothe user.

Other aspects, features, and advantages of the present patentapplication will become apparent from the following detaileddescription, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments are disclosed, by way of example only, withreference to the accompanying schematic drawings in which correspondingreference symbols indicate corresponding parts, in which

FIG. 1 shows a front elevational view of a chair with a suspended seatpan allowing for an omnidirectional movement of the seat pan inaccordance with an embodiment of the present patent application;

FIG. 2 shows a left side elevational view of the chair of FIG. 1;

FIGS. 3A and 3B show front elevational views of the chair when the seatpan or seat base member of the chair is in a left side position and in aright side position, respectively, in accordance with an embodiment ofthe present patent application;

FIGS. 3C and 3D show partial, up-close front elevational views of thechair when the seat base member is in a center position in accordancewith an embodiment of the present patent application;

FIG. 3E shows a partial, up-close front elevational view of the chairwhen the seat base member is in in the right side position in accordancewith an embodiment of the present patent application;

FIGS. 4A and 4E show left side elevational views of the chair when theseat base member is in a rearward position and FIGS. 4B and 4F show leftside elevational views of the chair when the seat base member is in in aforward position in accordance with an embodiment of the present patentapplication;

FIGS. 4C and 4D show partial, up-close left side elevational views ofthe chair when the seat base member is in the rearward position and inthe forward position, respectively, in accordance with an embodiment ofthe present patent application;

FIGS. 5A and 5B show front elevational views of the chair when the seatbase member is in side tilted or angled (downwardly at the left side anddownwardly at the right side, respectively) positions in accordance withan embodiment of the present patent application;

FIGS. 6A and 6B show left side elevational views of the chair when theseat base member is in front to back tilted or angled (downwardly at theback/rear side and downwardly at the front side, respectively) positionsin accordance with an embodiment of the present patent application;

FIG. 7 shows perspective views of portions of a suspension assembly andthe seat base member being attached to the portions of the suspensionassembly in accordance with an embodiment of the present patentapplication;

FIG. 8 shows a perspective view of the chair, with some portions of thechair removed for sake of clarity, in accordance with an embodiment ofthe present patent application;

FIG. 9 shows a perspective view of an exemplary chair, with someportions of the chair removed for sake of clarity, in accordance with anembodiment of the present patent application;

FIG. 10 shows a perspective view of another exemplary chair, with someportions of the chair removed for sake of clarity, in accordance with anembodiment of the present patent application;

FIGS. 10A-10C show views of an exemplary lock or ratchet assembly thatis used to control the length of suspension members that suspend theseat base member of the chair in accordance with an embodiment of thepresent patent application;

FIGS. 10D-10G show views of an exemplary drive assembly that is used tolengthen or shorten the suspension members of the chair in accordancewith an embodiment of the present patent application;

FIGS. 10H-10J show views of an exemplary movement limiter assembly thatis used to control the movement of the seat base member of the chair inaccordance with an embodiment of the present patent application;

FIGS. 10K-10N show views of disks with elongated openings that are usedin the movement limiter assembly and their various configurations,respectively in accordance with an embodiment of the present patentapplication;

FIG. 10P shows a left side elevational view of the chair with aninteraction element that links the seat base member to the seat backmember or support frame member in accordance with an embodiment of thepresent patent application;

FIGS. 10Q and 10R show left side elevational views of the chair with anexemplary seat base member locking mechanism in a locked and an unlockedconfiguration, respectively, in accordance with an embodiment of thepresent patent application;

FIG. 10S shows a left side elevational view of the chair with theexemplary seat base member locking mechanism in the locked configurationwhen the user is seated in a reclined position in accordance with anembodiment of the present patent application;

FIG. 11 shows a front elevational view of a chair with a moveable lumbarsupport member in accordance with an embodiment of the present patentapplication;

FIG. 12 shows a left side elevational view of the chair of FIG. 11;

FIGS. 13A and 13D show left side elevational views of the chair, whereinthe lumbar support member is in a first position, FIG. 13B shows a leftside elevational view of the chair, wherein the lumbar support member isin an intermediate position, and FIGS. 13C and 13E show left sideelevational views of the chair, wherein the lumbar support member is ina second position in accordance with an embodiment of the present patentapplication;

FIGS. 14A-C show views of a system configured to move the lumbar supportmember between the first position and the second position in accordancewith an embodiment of the present patent application;

FIGS. 15 and 16 show perspective views of an exemplary chair with themoveable lumbar support member, where FIG. 15 shows the lumbar supportmember in the first position and FIG. 16 shows the lumber support memberin the second position in accordance with an embodiment of the presentpatent application;

FIGS. 17 and 18 show left side elevational views of the chair when theseat base member is in a rearward position and in a forward position,respectively, and the lumbar support member is moving along with theseat base member in accordance with an embodiment of the present patentapplication;

FIGS. 19, 20, 21, and 22 show a perspective view, a rear elevationalview, a left side elevational view, and a front elevational view of anexemplary chair in accordance with another embodiment of the presentpatent application;

FIGS. 23, 24, 25, and 26 show a perspective view, a rear elevationalview, a left side elevational view, and a front elevational view of thechair, with some portions of the chair removed for sake of clarity, inaccordance with another embodiment of the present patent application;

FIGS. 27 and 28 show a front elevational view and a left sideelevational view of the chair with an ergonomic position sensingarrangement in accordance with an embodiment of the present patentapplication;

FIGS. 29 and 30 show left side elevational views of the chair with theergonomic position sensing arrangement in accordance with an embodimentof the present patent application;

FIGS. 31 and 32 show sensor systems used with the ergonomic positionsensing arrangement in accordance with an embodiment of the presentpatent application;

FIGS. 33-35 show left side elevational views of the chair with theergonomic position sensing arrangement and the sensor fields of thesensor systems in accordance with an embodiment of the present patentapplication;

FIGS. 36 and 37 show indicator systems used with the ergonomic positionsensing arrangement in accordance with an embodiment of the presentpatent application;

FIG. 38 shows a perspective view of a chair configured to allow for anomnidirectional movement of its seat pan member in accordance withanother embodiment of the present patent application;

FIG. 39 shows a left side elevational view of the chair of FIG. 38;

FIG. 40 shows an exploded view of the seat pan member of the chair ofFIG. 38;

FIG. 41 shows an assembled view of the seat pan member of the chair ofFIG. 38;

FIG. 42 shows a partial bottom plan view of a front portion of the seatpan member of the chair of FIG. 38;

FIG. 43 shows a partial perspective view of a rear portion of the seatpan member of the chair of FIG. 38;

FIGS. 44 and 45 show front and rear elevational views of a seat backmember of the chair of FIG. 38;

FIGS. 46 and 47 show partial cross-sectional side views of the chair ofFIG. 38 and a seat pan lock assembly for the chair, where the seat panlock assembly is in an unlocked configuration in FIG. 46 and is in alocked configuration in FIG. 47;

FIGS. 48 and 49 show partial side perspective views of the chair of FIG.38, where the seat pan lock assembly is in the unlocked configuration inFIG. 48 and is in a locked configuration in FIG. 49;

FIGS. 50 and 51 show partial rear perspective views of the chair of FIG.38, where the seat pan lock assembly is in the unlocked configuration inFIG. 50 and is in a locked configuration in FIG. 51;

FIG. 52 shows an exploded view of the seat pan lock assembly inaccordance with an embodiment of the present patent application;

FIG. 53 shows a cross-sectional view of the seat pan lock assembly inaccordance with an embodiment of the present patent application, wherethe seat pan lock assembly is shown in the locked and unlockedconfiguration and some portions of the chair are not shown for sake ofclarity;

FIG. 53a shows a partial rear view of the seat pan lock assembly inaccordance with an embodiment of the present patent application, wheresome portions of the chair are not shown for sake of clarity;

FIGS. 54-56 show partial perspective views of the seat pan lock assemblyin accordance with various embodiments of the present patentapplication;

FIG. 57 shows a perspective view of an adjustable armrest assembly inaccordance with an embodiment of the present patent application, wherethe armrest is in its raised configuration;

FIG. 58 shows another perspective view of the adjustable armrestassembly, where the armrest is in an intermediate configuration betweenits raised and lowered configurations;

FIG. 59 shows another perspective view of the adjustable armrestassembly, where the armrest is in its lowered configuration;

FIG. 60 shows an assembled view of the adjustable armrest assembly inaccordance with an embodiment of the present patent application;

FIG. 61 shows an exploded view of the adjustable armrest assembly inaccordance with an embodiment of the present patent application;

FIG. 62 shows a side view of an adjustable armrest assembly inaccordance with another embodiment of the present patent application,where the armrest is shown in its raised configuration and where someportions of the chair are not shown for sake of clarity;

FIG. 63 shows a side view of the adjustable armrest assembly of FIG. 62,where the armrest is in its lowered configuration;

FIGS. 64 and 65 show prior art tilt mechanism and a tilt mechanism forthe chair in accordance with an embodiment of the present patentapplication;

FIG. 66 shows a single adjustment mechanism for tilt mechanism of thechair in accordance with an embodiment of the present patentapplication; and

FIGS. 67(a)-67(e) show various configurations of the movement supportmembers of the chair in accordance with an embodiment of the presentpatent application.

DETAILED DESCRIPTION OF THE DRAWINGS

The present patent application provides a chair 10 with ergonomic motionfeatures. For example, the chair 10 includes a suspended seat pan 12allowing for a multidirectional movement of the seat pan 12. Theconfiguration of the seat pan 12 provides a multitude of optimalpositions allowing the user to switch to a secondary primary sittingposition or to be encouraged to move, transitioning through everchanging sitting positions (e.g., FIGS. 3A, 3B, 4A, 4B, 5A, 5B, 6A and6B). This encouragement of dynamic movement allows the user not to bestagnant when seated, while still be properly supported by the chair 10.The chair 10 may also include a moveable lumbar support member 22 thatmoves forward when actuated (either manually or automatically) allowingthe user to sit in a more forwardly position on the seat pan 12.Research has shown that the forwardly seated position is beneficial asthis forwardly seated position allows the user to sit in a more alertposture and in a feet flat on the floor position. The moveable lumbarsupport member 22 provides support to the lower back of the user whenthe user is in this forwardly seated position.

FIGS. 1 and 2 show the chair 10 that includes the seat base member orthe seat pan 12, a seat base support member 14, a suspension assembly 16and an actuator 18. The present patent application relates to sittingproducts, for example, chairs, office chairs and or ergonomic chairs.

The chair 10 may include a seat back member 20 for supporting the backof the user while seated in the chair 10. The seat back member 20 may bemoveable (pivotable or tiltable) between a normal, upright position anda plurality of rearwardly (with respect to the seat base support member14 or a base assembly 30) tilted positions. Each of the plurality ofrearwardly tilted positions may have a different degree of tilt of theseat back member 20. The user, in accordance with his/her own comfortrequirement(s), may select the degree of tilt of the seat back member20. The chair 10 may include a lock mechanism that may releasably lockthe seat back member 20 in either the normal, upright position or one ofthe rearwardly, tilted positions. The seat back member 20 may include alumbar support member 22 for supporting the lumbar area of the userwhile seated in the chair 10. In one embodiment, the seat back member 20and/or lumbar support member 22 are optional.

The chair 10 may include the base assembly 30 that includes an upright,support column member 32 and a plurality of base members 34 extendingradially from a lower portion 33 of the upright support column member32. In the illustrated embodiment, the base assembly 30 includes fivebase members 34 (i.e., legs). However, the number of base members 34 canvary as long as the number of base members is sufficient to providestability to the chair 10. Each of the plurality of base members 34 hasa caster wheel 36 positioned at its free end 35 thereof so as tofacilitate the movement of the chair 10 along a surface (e.g., floor orground). The configuration and design of the base assembly 30 is notlimiting, and any design to stably support the chair on the surface maybe used. In one embodiment, the caster wheels 36 are optional.

The chair 10 may optionally include headrest 38. In one embodiment, theheadrest 38 may be positioned above the seat back member 20. Theheadrest 38 may be adjustable in both its angle and its height. Forexample, the headrest 38 may be configured to be moved forward,rearward, at an angle, upward and/or downward to support the user's head(when the user is seated in the chair 10). The chair 10 may optionallyinclude a pair of armrests 40. The armrests 40 are positioned on sidesof the chair 10. The armrests 40 may be adjustable in their height sothat the height of the armrests 40 is adjusted to support the user'sarms. In one embodiment, the armrest 40 may be stationary. In anotherembodiment, the armrests 40 may be movable or pivotable between ahorizontal, use (armrest) position (as shown in FIGS. 1 and 2) and avertical, stored position (i.e., flush with the seat back member 20).

In one embodiment, the headrest 38 and the armrests 40 may be cushioned(with varying firmness and contours) to provide increased comfort to theuser's head, neck and the arms, respectively. The headrest 38 andarmrests 40 may be ergonomically designed to provide comfort and supportto the user's neck, head and arms, respectively. The headrest 38 and thearmrest 40 may include simple padded material, contoured padded materialand engineered breathable mesh material to further provide comfort andsupport to the user's neck, head and the arms, respectively.

The chair 10 may include a height adjustment mechanism 42 configured foradjusting the height of the seat base support member 14 from the floor.In one embodiment, the height adjustment mechanism 42 may include ahydraulic mechanism, pneumatic mechanism, pressurized gas mechanism ormechanical mechanism (e.g., screw shaft assembly) for adjusting thevertical height of the seat base member 13 from the floor. In theillustrated embodiment, the height adjustment mechanism 42 includes apneumatic cylinder assembly (i.e., gas charged piston). In oneembodiment, the adjustment of the height of the seat base support member14 from the floor also adjusts the height of the seat base member 12from the floor.

In one embodiment, the chair 10 may include a tilt adjustment mechanism70 configured for adjusting the tilt of the seat base support member 14with respect to the base assembly 30. In one embodiment, the tiltadjustment mechanism 70 is a rotational tilt mechanism that uses anadjustable torsional spring for adjusting the tilt of the seat pan orbase member 12.

In the illustrated embodiment, the height adjustment mechanism 42includes a height adjustment lever or button 44 for adjusting the heightof the seat base support member 14 from the floor. In one embodiment,the chair 10 may include one or more tilt adjustment levers or buttons46 for adjusting the tilt of the seat back member 20 and/or the seatbase member 12. The adjustment button(s) or lever(s) may be easilyactuated by the user seated in the chair 10 in order to operate theheight adjustment mechanism 42 and/or the tilt adjustment mechanism 70.

The chair may include a back recline spring 80 (as clearly shown in FIG.12). In one embodiment, the back recline spring 80 may be operativelyconnected between the seat back member 20 and the adjustment mechanism42. In one embodiment, the back recline spring 80 may be configured toprovide resistance to the reclining (tiltable) movement of the seat backmember 20. In one embodiment, the seat back member 20 may be connectedto a support frame member 82. In one embodiment, the support framemember 82 may have a hollow tubular cross-section. In one embodiment,the support frame member 82 extends at least partially along (behind)the seat back member 20 and at least partially (under) the seat basemember 12. In one embodiment, the support frame member 82 may beoperatively connected to the pneumatic cylinder 42.

In one embodiment, the height of the seat back member 20 and/or thelumbar support member 22 with respect to the seat base member 12 may beadjusted vertically along the support frame member 82. For example,carriages or similar mechanisms 102 and 104 may be positioned on rearsurfaces 106 and 108 of the seat back member 20 and the lumbar supportmember 22, respectively. The carriages or similar mechanisms 102 and 104are configured to slide up and down the support frame member 82 toadjust the height of the seat back member 20 and the lumbar supportmember 22, respectively.

The seat base member 12 may be a substantially rigid structural memberconfigured to support the weight of the user seated in the chair 10. Theseat base member 12 is constructed to support thighs and bottom of theuser while seated in the chair 10.

In one embodiment, the seat base member 12 and the seat back member 20(along with the lumbar support member 22) may include simple paddedmaterial or contoured padded material as shown in the exemplary chair ofFIG. 10. In another embodiment, each of the seat base member 12 and theseat back member 20 (along with the lumbar support member 22) mayinclude a peripheral frame member and engineered (contour forming)breathable mesh (e.g., elastomeric) material as shown in the exemplarychair of FIG. 9.

In one embodiment, the vertical height of the seat base support member14 from the floor and the tilt angle of the seat base support member 14with respect to the base assembly 30 may be adjusted by the user. Theseat base support member 14 may also be configured to be rotatable withrespect to the base assembly 30 to allow the user to turn/revolve whileseated in the chair 10.

Referring to FIG. 7 (lower), in one embodiment, the seat base supportmember 14 may be part of the suspension assembly and may be referred toas the suspension frame member. In one embodiment, the seat base supportmember 14 may include two generally U-shaped members 72 and 74 that areconnected to each other by two transverse members 76 and 78. In oneembodiment, the two transverse members 76 and 78 are optional as shownin the exemplary suspension assembly of FIG. 8. In one embodiment, asshown in FIG. 7, the two generally U-shaped members 72 and 74 and thetwo transverse members 76 and 78 of the seat base support member 14 areconfigured to support the seat base member 12 thereon. In oneembodiment, the seat base support member 14 may be positioned on thebase assembly 30.

The suspension assembly 16 is operatively connected to the seat basemember 12 and the seat base support member 14. Referring to FIGS. 7-10,the suspension assembly 16 includes a first suspension member 48, asecond suspension member 50, and an optional movement limiter assembly60. The seat base member 12 is constructed and arranged to be suspendedby the first suspension member 48, the second suspension member 50 andthe movement limiter assembly 60. In one embodiment, the movementlimiter assembly 60 is a centering device that biases the seat basemember to the center (or a center position).

In one embodiment, the first suspension member 48 may include twosuspension members that are interconnected to act as one suspensionmember. In one embodiment, the second suspension member 50 may includetwo suspension members that are interconnected to act as one suspensionmember. For example, the two suspension members of the first suspensionmember 48 and the two suspension members of the second suspension member50 are configured to function as four separate suspension members. Inone embodiment, the four suspension members may be in the form of cablesattached or connected to the seat pan frame 14.

In one embodiment, the second suspension member 50 may be attached tothe frame member 74. In one embodiment, the frame member 74 may beoptionally attached to the seat back member 20. For example, when theframe member 74 is attached to seat back member 20, the frame member 74may be configured to have an open U shaped configuration so as to havenearly or substantially flat configuration. In one embodiment, the framemember 74 may be completely eliminated from the chair 10 and the secondsuspension member 50 may be directly suspended to the seat back member20 (e.g., using simple hardware).

Referring to FIGS. 10A-10G, the suspension assembly 16 may also includea drive system 500 that is operatively connected to the actuator 18, thefirst suspension member 48, and the second suspension member 50 suchthat actuation of the actuator 18, by the user, operates the drivesystem 500 to control the first suspension member 48 and the secondsuspension member 50. In one embodiment, the drive system 500 mayinclude a spring and pulley system.

In one embodiment, as shown in FIGS. 10A-10G, the drive system 500includes a pulley or cam 502, a spring 504, and a ratchet assembly 506.The spring 504 may be a torsion spring that is configured to dampen themovement of the cam or pulley 502. In one embodiment, the spring 504 isoptional.

The ratchet assembly 506 may be configured to lock the length of thecable or the suspension members 48 or 50 at a desired position untilreleased. For example, referring to FIGS. 10A-C, the ratchet assembly506 may include a ratchet wheel 508 and a locking pawl 512. The ratchetwheel 508 is configured to be rotatable with and attached to the pulley502, and includes ratchet teeth 510. The locking pawl 512 includes alock surface 514 and a pivot point 516 on which the locking pawl 512pivots for engagement with the ratchet wheel 508. The lock surface 514is adapted for engagement with a ratchet tooth 510 of the ratchet wheel508. FIG. 10A shows the lock surface 514 of the locking pawl 512 beingengaged with the ratchet tooth 510 of the ratchet wheel 508 so as toprevent or inhibit rotation of the ratchet wheel 508 and the pulley 502.In this position, the ratchet assembly 506 is configured to lock thelength of the cable or the suspension members 48 or 50 at a desiredposition.

When the suspended seat base member 12 is moved by the user, thesuspension members 48 or 50 on which the seat base member 12 issuspended are lengthened (or shortened) by rotating the pulley 502 onwhich the suspension members 48 or 50 are wound. That is, the suspensionmembers 48 or 50 are wound up around the pulley 502 and the pulley 502is rotated when the suspension members 48 or 50 are pulled. Rotation ofthe pulley 502 causes rotation of the ratchet wheel 508 attachedthereto. This movement causes the pawl 512 to pivot away from theratchet wheel 508, disengage the locking pawl 512 from the ratchet teeth510, and allow the pulley 502 (and the ratchet wheel 508 attachedthereto) to rotate freely in the direction of an arrow CC. FIG. 10Bshows the ratchet assembly 506 during the free rotation of the pulley502 (and the ratchet wheel 508 attached thereto). Once the desiredposition of the seat base member 12 is achieved (and there is no furtherlengthening of the cables and/or rotation of the pulley 502), the pawl512 is configured to pivot back into engagement with the ratchet teeth510 so as to prevent or inhibit rotation of the ratchet wheel 508 andthe pulley 502 as shown in FIG. 10C.

Referring to FIGS. 10D-10G, rotating the cam or pulley 502 is configuredto lengthen or shorten the cable or suspension members 48 or 50 thatsuspend the seat base member 12. FIG. 10E shows winding direction asshown by an arrow W in which the cable or suspension members 48 or 50are wound for removing the slack therefrom. FIG. 10F shows unwindingdirection as shown by an arrow UW in which the cable or suspensionmembers 48 or 50 are unwound to allow for the adjustment of the seatbase member 12.

The actuator 18 may include user input devices such as dials, joysticks,slides, switches, and/or buttons. The actuator 18 may be a mechanicalactuator or an electro-mechanical actuator. The actuator may be a manualadjustment performed by a user seated in the chair 10. In oneembodiment, a single actuator may be configured to control both thefirst suspension member 48 and the second suspension member 50. Inanother embodiment, a plurality of actuators may be used, where each isconfigured to control each side of the each of the first suspensionmember 48 and the second suspension member 50.

Referring FIGS. 7-10, the first suspension member 48 is disposed at aforward position F of the chair 10 and the second suspension member 50is disposed at a rearward position R of the chair 10. In one embodiment,as shown in FIG. 8, the first suspension member 48 may include a firstsuspension base member 52 and two cable or linkage members 54 positionedat the ends of the first suspension base member 52. In one embodiment,the first suspension base member 52 may optionally be eliminated if thetwo linkage members 54 are directly attached to the seat pan frame 14.Similarly, the second suspension member 50 may include a secondsuspension base member 56 and two cable or linkage members 58 positionedat the ends of the second suspension base member 56. In one embodiment,the second suspension base member 56 may optionally be eliminated if thetwo linkage members 58 are directly attached to the seat pan frame 14.One end of each of the linkage or cable members is connected to thedrive system 500 and the other end of the linkage or cable members isconnected to the respective suspension base members. The suspension basemembers may be constructed to support the seat base member 12 thereon.

The movement limiter assembly 60 may be an adjustable self-centeringmechanism. In one embodiment, the movement limiter assembly 60 may bemultidirectional movement limiter assembly. In one embodiment, themovement limiter assembly 60 may be operatively connected to theactuator 18 such that, when the actuator 18 is actuated by user, themovement limiter assembly 60 may be tightened or loosened to control themovement of the seat base member 12.

The movement limiter assembly 60 may be configured to allow the seatbase member 12 to move from a near no movement position/condition (asshown in FIGS. 3C and 3D) to a more free uncontrolled motion and therebetween (as shown in FIGS. 3A, 3B, 4A, and 4B).

In one embodiment, the optional movement limiter assembly 60 may beconnected or assembled to the seat base member 12. The movement limiterassembly 60 may be configured to enable the user to tighten or loosenthe limiter assembly 60 so as to control the movement of the seat basemember 12. For example, by tightening the movement limiter assembly 60,the range of the movement of the seat base member 12 may be reduced orreturn force to center may be increased. In one embodiment, the seatbase member 12 may move freely with no resistance except when themovement limiter assembly 60 is engaged. In one embodiment, the movementlimiter assembly 60 is configured to provide some resistance such thatmore force is needed to move the seat base member 12 off its centerposition.

FIGS. 10H-10J show views of an exemplary movement limiter assembly 60that is used to control the movement of the seat base member 12. In oneembodiment, the movement limiter assembly 60 may include a cable 602attached to the base of the seat base member 12 at one end and is guidedthrough an eyelet 604 to a spool or reel 606. In one embodiment, thecable 602 is a flexible, elastomeric member that is attached to thespool 606 (with or without a torsion spring) at its other end. The spool606 is configured to rotate and shorten the length of the cable 604limiting the allowed movement of the seat base member 12 in alldirections. In one embodiment, the spool 606 may have a torsion springas to dampen the shock of reaching the limit of the allowed movement ofthe seat base member 12. FIGS. 10H and 10I show the cable 602 havingsome slack to provide the movement of the seat base member 12. FIG. 10Jshows the cable 602 being tightened to provide limited or no movement ofthe seat base member 12.

In one embodiment, the eyelet 604 may have a shaped configuration thatis configured to be adjusted to limit movement (forward and back, orright and left) of the seat base member 12. For example, as shown inFIGS. 10K-10N, the eyelet 604 may include disks 608, 610 with elongatedopenings 612, 614. That is, the eyelet 604 may be constructed from thestacked disk shapes 608, 610 that rotate around the elongated centeropenings 612, 614 allowing the cable 602 to move in a limited or freearrangement depending on the orientation of the elongated openings 612,614. The openings 612, 614 are oriented to create a controlling aperture621 to limit the movement of the cable 602. FIGS. 10M and 10N show twodifferent orientations of the elongated openings 612, 614 that providetwo different controlling apertures 621 to limit the movement of thecable 602.

In one embodiment, the movement limiter assembly 60 may be configured torestrict the movement of the seat base member 12 to a forward and backmovement or a side to side movement. In one embodiment, the movementlimiter assembly 60 may be configured to lock the seat base member 12 inplace (e.g., depending on the how the user engages the movementlimiters). In one embodiment, the movement limiter assembly 60 may beconfigured to limit the movement of the seat base member 12 in a forwardto back or a side to side direction.

As shown in FIG. 3C, the movement limiter assembly 60 is in a firstconfiguration to support the seat base member 12 in its near no movementposition/condition. When the actuator 18 is actuated by user, themovement limiter assembly 60 may be operated to move from this firstconfiguration (FIG. 3C) to a second configuration as shown in FIGS. 3A,3B, 3E, and 4A-4D. FIG. 3D shows the movement limiter assembly 60 in anintermediate position between its first configuration and its secondconfiguration.

The actuator 18 may be configured to operate the suspension assembly 16for translational or linear movement of the seat base member 12 withrespect to the seat base support member 14 along three mutuallyperpendicular axes (i.e., X, Y, and Z axes) and/or rotational movementthe seat base member 12 with respect to the seat base support member 14along the same three mutually perpendicular axes (i.e., X, Y, and Zaxes). That is, the actuator 18 may be configured to operate thesuspension assembly 16 for providing movement of the seat base member 12with respect to the seat base support member 14 in at least threedegrees of freedom.

The translational movement or displacement generally refers to linearmovement or displacement along these three mutually perpendicular X, Yand Z axes. For example, the translational movement along the X axisgenerally refers to a forward and backward movement in a horizontalseating plane. The translational movement along the Y axis generallyrefers to a left to right side movement in the horizontal seating plane.The translational movement along the Z axis generally refers to an upand down movement perpendicular to the horizontal seating plane.

The rotational movement or displacement generally refers to rotationabout these same three mutually perpendicular X, Y and Z axes. Therotation about the three mutually perpendicular X, Y and Z axes isgenerally referred to as yaw (Z-axis), pitch (Y-axis) and roll (X-axis).For example, the rotational movement about the X axis generally refersto a left or right side tilting movement. The rotational movement aboutthe Y axis generally refers to a forward or (rearward) backward tiltingmovement. The rotational movement about the Z axis generally refers to aleft or right turning movement.

In one embodiment, the seat base member 12 may have at least threedegrees of freedom. The degree of freedom generally refers to thefreedom of movement of the seat base member 12 in the three-dimensionalspace. In one embodiment, the at least three degrees of freedom mayinclude three translational movements of the seat base member 12 alongthese three mutually perpendicular X, Y and Z axes. In one embodiment,the at least three degrees of freedom include a forward and backwardmovement of the seat base member 12 on the X-axis, an up and downmovement of the seat base member 12 on the Z-axis, and a side to side(left to right) movement of the seat base member 12 on the Y-axis. Inanother embodiment, the at least three degrees of freedom may includetwo translational movements of the seat base member 12 along two of thethree mutually perpendicular X, Y and Z axes (i.e., the X and Y axes)and one rotation movement of the seat base member 12 about one of thesame three mutually perpendicular X, Y and Z axes (i.e., the Z-axis).

In one embodiment, the seat base member 12 may have at least fourdegrees of freedom. In one embodiment, the at least four degrees offreedom may include two translational movements of the seat base member12 along two of the three mutually perpendicular X, Y and Z axes and tworotational movements of the seat base member 12 about two of the samethree mutually perpendicular X, Y and Z axes. In another embodiment, theat least four degrees of freedom may include three translationalmovements of the seat base member 12 along the three mutuallyperpendicular X, Y and Z axes and one rotational movement of the seatbase member 12 about one of the same three mutually perpendicular X, Yand Z axes. In another embodiment, the at least four degrees of freedommay include three rotational movements of the seat base member about thethree mutually perpendicular X, Y and Z axes and one translationalmovement of the seat base member 12 along one of the same three mutuallyperpendicular X, Y and Z axes.

In one embodiment, the seat base member 12 may have at least fivedegrees of freedom. In one embodiment, the at least five degrees offreedom may include two translational movements of the seat base member12 along two of the three mutually perpendicular X, Y and Z axes andthree rotational movements of the seat base member 12 about three of thesame three mutually perpendicular X, Y and Z axes. In anotherembodiment, the at least five degrees of freedom may include threetranslational movements of the seat base member 12 along the threemutually perpendicular X, Y and Z axes and two rotational movements ofthe seat base member 12 about two of the same three mutuallyperpendicular X, Y and Z axes.

In one embodiment, the seat base member 12 may have six degrees offreedom. In one embodiment, the at least six degrees of freedom mayinclude three translational movements of the seat base member 12 alongthe three mutually perpendicular X, Y and Z axes and three rotationalmovements of the seat base member 12 about three of the same threemutually perpendicular X, Y and Z axes.

In one embodiment, the seat base member 12 may have five degrees offreedom (including three rotational movements of the seat base memberabout three mutually perpendicular X, Y and Z axes and two translationalmovements of the seat base member along the mutually perpendicular X andY axes) provided by the suspension assembly and may have verticaladjustment provided by the cylinder. In one embodiment, the seat basemember 12 may have four degrees of freedom (including two rotationalmovements of the seat base member about the two mutually perpendicular Xand Y axes and two translational movements of the seat base member 12along the two mutually perpendicular X and Y axes) provided by thesuspension assembly and may have vertical adjustment provided by thecylinder.

In one embodiment, when the actuator 18 is actuated by user, themovement limiter assembly 60 may be operated to control the movement ofthe seat base member 12 with respect to the seat back support member 14.For example, the movement limiter assembly 60 may be configured to allowthe seat base member 12 move to a rearward position as shown in FIGS.4A, 4C and 4E and to a forward position as shown in FIGS. 4B, 4D and 4F.The suspended seat pan 12 allows a user or person 802 to rock forward toa more alert and active position or moving position. The ability of theseat base member/pan 12 to move dynamically allows the user to varyhis/her body positioning in the chair 10 dynamically, as opposed to achair with a static fixed position for the seat pan. The movementlimiter assembly 60 may be configured to allow the seat base member 12move to a left side position as shown in FIG. 3A and to a right sideposition as shown in FIGS. 3B and 3E. As shown in FIGS. 3A, 3B, 3E, and4A-4D, the movement limiter assembly 60 may be in its extended (angularand flexible) configuration when the movement limiter assembly 60 issupporting the seat base member 12 in one of the forward, rearward, leftor right side positions. The movement limiter assembly 60 may beconfigured to lock the seat base member 12 in place in one of thepositioned described above.

When the user actuates the actuator 18, the actuator 18 may operate thedrive system 500 of the suspension assembly to either tighten or loosenthe cable or linkage members of the suspension assembly. In oneembodiment, tightening the cable or linkage members may also be referredto as shortening of the cable or linkage members and loosening the cableor linkage members may also be referred to as the lengthening of thecable or linkage members.

When the drive system 500 of the suspension assembly tightens both thecable or linkage members of the second suspension member 50 and loosensboth the cable or linkage members of the first suspension member 48, theseat base member 12 is moved to a forward tilt position as shown in FIG.6B. When the drive system 500 maintains both the cable or linkagemembers of the second suspension member 50 unchanged or the same andloosens both the cable or linkage members of the first suspension member48, the seat base member 12 is moved to the forward tilt position asshown in FIG. 6B. When the drive system 500 tightens the cable orlinkage members of the second suspension member 50 and maintains boththe cable or linkage members of the first suspension member 48 unchangedor the same, the seat base member 12 is moved to the forward tiltposition as shown in FIG. 6B.

When the drive system 500 tightens both the cable or linkage members ofthe first suspension member 48 and loosens both the cable or linkagemembers of the second suspension member 50, the seat base member 12 ismoved to a rearward tilt position as shown in FIG. 6A. When the drivesystem 500 maintains both the cable or linkage members of the firstsuspension member 48 unchanged or the same and loosens both the cable orlinkage members of the second suspension member 50, the seat base member12 is moved to the rearward tilt position as shown in FIG. 6A. When thedrive system 500 tightens both the cable or linkage members of the firstsuspension member 48 and maintains both the cable or linkage members ofthe second suspension member 50 unchanged or the same, the seat basemember 12 is moved to a rearward tilt position as shown in FIG. 6A.

When the drive system 500 tightens the right side cable or linkagemembers of the second suspension member 50 and the first suspensionmember 48 and loosens the left side cable or linkage members of thesecond suspension member 50 and the first suspension member 48, the seatbase member 12 is moved to a left side tilt position as shown in FIG.5A. When the drive system 500 maintains the right side cable or linkagemembers of the second suspension member 50 and the first suspensionmember 48 unchanged or the same and loosens the left side cable orlinkage members of the second suspension member 50 and the firstsuspension member 48, the seat base member 12 is moved to the left sidetilt position as shown in FIG. 5A. When the drive system 500 tightensthe right side cable or linkage members of the second suspension member50 and the first suspension member 48 and maintains the left side cableor linkage members of the second suspension member 50 and the firstsuspension member 48 unchanged or the same, the seat base member 12 ismoved to the left side tilt position as shown in FIG. 5A.

When the drive system 500 tightens the left side cable or linkagemembers of the second suspension member 50 and the first suspensionmember 48 and loosens the right side cable or linkage members of thesecond suspension member 50 and the first suspension member 48, the seatbase member 12 is moved to a right side tilt position as shown in FIG.5B. When the drive system 500 maintains the left side cable or linkagemembers of the second suspension member 50 and the first suspensionmember 48 unchanged or the same and loosens the right side cable orlinkage members of the second suspension member 50 and the firstsuspension member 48, the seat base member 12 is moved to the right sidetilt position as shown in FIG. 5B. When the drive system 500 tightensthe left side cable or linkage members of the second suspension member50 and the first suspension member 48 and maintains the right side cableor linkage members of the second suspension member 50 and the firstsuspension member 48 unchanged or the same, the seat base member 12 ismoved to the right side tilt position as shown in FIG. 5B. The actuator18 and the drive system 500 are optional and need not be included in allthe embodiments of the present patent application.

In one embodiment, the lumbar support member 22 is operatively connectedto the seat base member 12 so as to move the lumbar support member 22along with the seat base member 12. That is, the lumbar support portion22 may be configured to be moved with the suspended multidirectionalseat base member 12 if desired. In another embodiment, the lumbarsupport member 22 is not operatively connected to the seat base member12 so that the lumbar support member 22 does not move along with theseat base member 12.

In one embodiment, the multidirectional seat base member 12 may beconnected to the seat back member 20 so the seat base member 12 moves asthe seat back member 20 is reclined backwards. For example, the chair 10may include an interaction element 702 as shown in FIG. 10P to link themultidirectional seat base member 12 to the seat back member 20 orsupport frame member 82. In one embodiment, the interaction element 702may include members 704 and 706 that may act together as a singlemember. In one embodiment, the members 704 and 706 may be in the form ofa flexible member or a cable. In another embodiment, themultidirectional seat base member 12 may be not connected to the seatback member 20.

The chair 10 may include a controlling and adjustment mechanism that maybe configured to regulate the return of the seat base member 12 to itsnormal, centered position (as shown in FIGS. 3C and 3D). In oneembodiment, the controlling and adjustment mechanism may be configuredto regulate the suspension assembly for front to back (pitch), andlateral (roll) positioning. In one embodiment, the controlling andadjustment mechanism may be configured to receive a signal from theactuator 18 when it is actuated by the user. In response to the signal,the controlling and adjustment mechanism may be configured to operatethe suspension assembly to move the seat base member 12.

FIGS. 10Q and 10R show views of a seat base member locking mechanism 902in a locked and an unlocked configuration, respectively. When in thelocked configuration, the seat base member 12 does not move, is lockedand does not provide any movement. When in the unlocked configuration,the seat base member 12 provides free uncontrolled movement of the seatbase member 12 in all directions (except when the movement limiterassembly 60 is engaged).

In one embodiment, the seat base member locking mechanism 902 includes alock member 904 and a lock surface 906. The lock member 904 may bespring biased and may be in the form of a pin member. The lock surface906 may be disposed on the seat base member 12 and may be in the form ofa notch, a slot or an opening. When the seat base member lockingmechanism 902 is in the unlocked configuration, a force against the lockmember 904 causes the lock member 904 to retract and compress thespring. When the (compression) force is released (by actuation of abutton 910 by a user), the (expansion) force of the spring causes thelock member 604 to be pushed outwardly to engage with the lock surface906 so as to lock the seat base member 12 in the locked configuration.

FIG. 10S shows a view of the seat base member locking mechanism 902 inthe locked configuration when the user is seated in a reclined position(when the user's back is engaged with the seat back member). When theuser is seated in a forward position without engaging his/her back tothe seat back member, a full seat pan movement is provided by the seatbase member 12 in the unlocked configuration.

It is contemplated that, in one embodiment, the seat back member 20and/or the lumbar support 22 may be completely eliminated from the chair10 to provide the user with a more challenging, advanced or athleticseating experience. In such an embodiment, the user is provided with aseating arrangement with a free moving seat pan 12 and without seat backor armrests. For example, the seating arrangement may include a stooltype seat.

In one embodiment, the chair 10 may provide a configuration where theuser may raise the armrests 40 of the chair 10 up or the user may movethe armrests 40 down or away. In another embodiment, the armrests 40 maybe completely eliminated from the chair 10.

Referring to FIGS. 11 and 12, the chair 10 may include a lumbar supportassembly 24 that is operatively connected to the lumbar support member22 and configured for moving the lumbar support member 22, with respectto the seat base member 12 and the seat back member 20, between a firstposition (as shown in FIG. 12) and a second position (as shown in FIGS.13C and 13E). That is, when actuated (manually and automatically), thelumbar support assembly 24 is configured to move the lumbar supportmember 22 forward allowing the user to sit in a more forwardly positionon the seat base member 12 while being supported by the lumbar supportmember 22.

When the lumbar support member 22 is in the second position, the lumbarsupport member 22 is positioned forwardly, in a direction toward theseated user's lower back, relative to the seat back member 20 so as toenable the user 802 to be seated forwardly on the seat base member 12 asshown in FIG. 13E. The actuator 18′ may be configured to operate thelumbar support assembly 24 for movement of the lumbar support member 22between the first position and the second position.

In one embodiment, as shown in FIGS. 11, 12, 13A and 13D, the firstposition is an initial position of the lumber support member 22 when theuser 802 is seated normally (with user's back supported by the seat backmember 20) on the seat base member 12. In one embodiment, the secondposition is a position of the lumbar support member 22 when the user 802is seated forwardly on the seat base member 12. The forward or thesecond position may be set (saved in a memory device of the chair 10) asto allow the user 802 to repeatedly obtain the most preferred position.The forward or second position allows the user 802 to sit in more alertposition and in a feet flat on the floor position. In one embodiment, asshown in FIG. 13B, the lumbar support member 22 may be configured tomove in the direction of the arrow M from the first position to thesecond position.

In one embodiment, the lumbar support member 22 may have an intermediateposition between the first and the second positions. In one embodiment,the lumbar support member 22 may have a plurality of intermediatepositions between the first and the second positions. In one embodiment,the seat base member 12 is first adjusted and locked in the desiredposition. The lumbar support member 22 may then be moved or adjusted tomeet the user 802 wherever the user 802 decides to sit upon the seatbase member 12.

The lumbar support assembly 24 may include pneumatic, spring ormotorized actuation device 86. In the illustrated embodiment, the lumbarsupport assembly 24 includes a pneumatic actuation device 86. In oneembodiment, the lumbar support assembly 24 may also include a lumbarsupport frame member 84. In one embodiment, the lumbar support framemember 84 may have a hollow tubular cross-sectional configuration. Thelumbar support frame member 84 may be operatively connected to theactuation device 86 and to the lumbar support member 22 such that, whenthe user 802 actuates the actuator 18′, the actuator 18′ operates thepneumatic actuation device 86 to move the lumbar support member 22, viathe lumbar support frame member 84, between its first and secondpositions.

FIGS. 17 and 18 show left side elevational views of the chair 10 whenthe seat base member 12 is in a rearward position and in a forwardposition, respectively, and the lumbar support member 22 is moving alongwith the seat base member 12. This configuration allows the user 802 torock forward to a more alert and active position or moving position.

Referring to FIGS. 14A-C, the chair 10 may include a linear guideassembly 90 that includes a collet 94 and a linear glide member 96. Thecollet may be adapted to be carried by the linear glide member formovement between a first and a second position relative to the linearglide member. In one embodiment, the travel limit adjustable collet isshown in FIGS. 14A-C.

FIG. 14A shows the collet 94 stopping the linear glide member 96 at agiven position. FIG. 14B shows a lever and spring assembly 92 thatallows a pin member 98 to retract allowing the linear glide member 96 tomove to the second position. FIG. 14C shows the lever and springassembly 92 that allows the pin member 98 to retract allowing the linearglide member 96 to move to the third position.

The chair 10 also includes the memory device that allows the user todecide where their optimal (lumbar support member) position is relativeto the seat base member 12. Once the user is at their optimal (lumbarsupport member) position and force of engagement, the user presses alever (by mechanical, pneumatic or electro mechanical means) to engage aset stop.

In one embodiment, travel limit and range of engagement may be adjustedand defined by the user. Once the lumbar support member 24 is in theuser preferred or desired (lumbar support member) position, the colletmay be locked onto the linear glide member so that the unit, whenactivated returns to the same location. The final and potentiallyseveral positions may be set depending on the number of collets used andby adding a mechanical (e.g., lever and spring actuation assembly 92) orelectromechanical (e.g., solenoid) actuated assembly.

In one embodiment, a spring tension and/or air piston force may beadjusted so the lumbar support member 24 may be engaged to press gently(adjustable force) on the user's lower back if desired (i.e., no lockedposition).

FIGS. 19, 20, 21, and 22 show a perspective view, a rear elevationalview, a left side elevational view, and a front elevational view of anexemplary chair and FIGS. 23, 24, 25, and 26 show a perspective view, arear elevational view, a left side elevational view, and a frontelevational view of the chair, with some portions of the chair removedfor sake of clarity, in accordance with another embodiment of thepresent patent application. Components of the chair depicted in FIGS.19-26 may be similar to corresponding component of the chair depicted inFIGS. 1-10S, and as such, are labeled identically to those components ofthe chair 10.

FIGS. 27-30 show various views of the chair 10 with an ergonomicposition sensor or sensing arrangement 402. In one embodiment, the chair10 may include an embedded (i.e., built into the chair) ergonomicposition sensing arrangement. In one embodiment, the ergonomic positionsensing arrangement 402 is embedded into the underside frame structureof the chair. In another embodiment, the chair may include a separatelyattached (i.e., added to the chair later on (retrofitted)) ergonomicposition sensing arrangement. In one embodiment, the ergonomic positionsensing arrangement 402 is configured to be retrofitted to the chair'sframe. For example, the sensor array may be an optional element that canbe applied to any office chair. The retrofitted ergonomic positionsensing arrangement 402 is configured to project the sensor zonesthrough the chair and create a sensing field. The sensor array isconfigured to sense through the fabric material of the seat back memberand/or the seat pan/base member 12 of the chair 10.

In one embodiment, the ergonomic position sensing arrangement 402 mayinclude capacitance sensor systems 404 a and 404 b. Each of thecapacitance sensor systems 404 a and 404 b include one or morecapacitance sensor 406 a and one or more attachment straps 410 that areconfigured to attach the respective capacitance sensor(s) 406 a toportions of the chair 10. The attachment straps 410 may include one ormore attachment portions 412 (e.g., end hooks) adapted to enable theattachment of the capacitance sensors 406 a to the chair. In oneembodiment, the attachment straps or members 410 may be elastomericstraps or members. In another embodiment, hook and loop type fasteningarrangements (e.g., Velcro®) may be used to attach the respectivecapacitance sensor(s) 406 a to portions of the chair 10.

The sensors due to their sensing nature of creating sensing fields, suchas capacitive fields, are configured to sense each other to detect notjust the presence of a user or their sitting position, but also themovement of the user's body and/or their engagement and active use ofthe dynamic movements when seated in the chair.

The capacitance sensor system 404 b and its associated capacitancesensor(s) 406 a are attached to the seat base member 12 via theattachment straps 410 and attachment portions 412 so as to sense theposition of the user on the seat base member 12. The capacitance sensorsystem 404 a and its associated capacitance sensor(s) 406 a are attachedto the seat back member via the attachment straps 410 and attachmentportions 412 so as to sense the position of the user's back on the seatback member.

In one embodiment, as shown in FIGS. 27-30, the capacitance sensorsystem 404 a may include two capacitance sensors, one for sensing thelumbar area of the user and the other for sensing the upper back area ofthe user. In another embodiment, as shown in FIG. 30, the capacitancesensor system 404 a may include three capacitance sensors, the first onefor sensing the lumbar area of the user, the second one for sensing theupper back area of the user, and the third one for sensing the head areaof the user. In yet another embodiment, the number of capacitancesensors in the capacitance sensor system may vary.

In one embodiment, as shown in FIGS. 28-30, the capacitance sensorsystem 404 a may include two separate capacitance sensor sub-systems 416a, 416 b that are connected to each other. Each capacitance sensorsub-system 416 a, 416 b may include one or more capacitance sensor(s)406 a, the attachment straps 410 and the attachment portions 412. Inanother embodiment, as shown in FIG. 32, the capacitance sensor system404 a may include a single system having one or more capacitancesensor(s) 406 a, the attachment straps 410 and the attachment portions412

In one embodiment, the capacitance field of the capacitance sensorsystems 404 a and 404 b is configured to travel a given distance throughthe seat and back cushion or mesh of the chair 10. FIGS. 33-35 show leftside elevational views of the chair 10 with the ergonomic positionsensing system 402 and its sensor fields 431. The sensing fielddetermines if the user is sitting in the chair and how the user issitting in the chair.

The sensor arrangement (or array) may be configured to sense thepresence of the user, their sitting position(s) and/or their weightdistribution. The sensor arrangement may also be configured tocontinuously sense the movement of the user so as to determine whetherthe user is sitting in a correct (or optimal) position and/or movingbetween the various sitting positions correctly.

In one embodiment, the signal from the sensor arrangement may betransmitted wirelessly (e.g., via a Bluetooth low energy module) or in awired manner to a receiver module of a controller. In response to thereceived signal, the controller is configured to provide an indicationto the user about their users sitting “health”. In one embodiment, theindication is a visual indication. The controller may be configured toprovide various color indications to the user based on the user'ssitting postures. The colors may change slowly allowing the user toconstantly observe (e.g., in a non-intrusive display or form) theircurrent ergonomic health. For example, the controller may be configuredto provide a purple or green color indication for a good, healthysitting posture, a yellow or orange color indication for moving toanother sitting posture (or take a break from the current sittingposture) and a red color indication for an unhealthy, wrong sittingposture and for the user to get up and move around.

FIGS. 36 and 37 show indicator systems 421 and 423 that are used withthe ergonomic position sensing system 402. Ergonomic heath indicatorsystems 421 and 423 may be configured to display (e.g., light up colorson a display) the user's current sitting position's ergonomic health asdetected by the sensor system(s) 406 a. Ergonomic heath indicatorsystems 421 and 423 may also be configured to display information to theuser such as when to take a break and when get up and walk around.Ergonomic heath indicator systems 421 and 423 may also be configured todisplay information to the user such as their sitting time as tracked bythe control system associated with the sensor system(s) 406 a. Ergonomicheath indicator systems 421 and 423 may also be configured to display tothe user other ergonomic sitting heath indicator information.

The ergonomic heath indicator system 421 may be positioned on a user'sdesk as shown in FIG. 36. The ergonomic heath indicator system 421 mayalso include a charging port configured to recharge a user's cellularphone 425. The ergonomic heath indicator system 421 may also includeadditional USB charging slots 427. In one embodiment, the same ergonomicfeedback information may be sent to the user's cellular phoneapplication by way of wireless communication such as but not limited to,WiFi, Bluetooth, Near Filed Communication (NFC) etc. so as to bedisplayed on a display 423 of the user's cellular phone 425. Anapplication on the user's cellular or cell phone may analyze thereceived data or information and visually display the health indicatorinformation.

The present patent application provides the multidirectional,dynamically moveable seat base member 12 so that the user sitting in thechair 10 not only moves forward and back together with the seat basemember 12, but also moves in a side to side as well as a circular orpivoting type movement with the seat base member 12. The present patentapplication takes into consideration more active sitting positions wherethe user is encouraged and supported to naturally move while stillseated creating a better holistic sitting experience. The present patentapplication uses the understandings of ergonomic sitting position theoryto provide the chair 10 which enable the user to move more naturally andto stimulate a more active posture while seated. The chair 10 of thepresent patent application also allows the user to do their daily taskswithout the undo harm one would usually incur from either lack ofmovement or improper support on a daily basis. The chair 10 of thepresent patent application thus bridges the ergonomic theory of safecontrolled seating and the desire to free the person to an unencumberedalbeit more liable type of office seating.

FIGS. 38-45 show a chair 1000 that is configured to allow amultidirectional movement of its seat pan member 1012 in accordance withanother embodiment of the present patent application. The configurationand the operation of the chair 1000 are same as those of the chairsdescribed with respect to FIGS. 1-37, except for some difference asnoted below.

In one embodiment, the chair 1000 includes the seat base member or theseat pan member 1012, a movement support frame 1014 (i.e., seat basesupport member), and at least two movement support members 1016 that areoperatively connected to the seat pan member 1012 and the movementsupport frame 1014. The at least two movement support members 1016 areconfigured to support the seat pan member 1012 in a floating manner fordynamic movement with respect to the movement support frame 1014 in atleast one degree of freedom in a horizontal seating plane. The at leasttwo movement support members 1016 are configured to support the seat panmember 1012 in a floating manner for dynamic movement with respect tothe movement support frame 1014 in at least one degree of freedom in thehorizontal seating plane. The horizontal seating plane generallyincludes a plane defined by the X and Y-axes.

As will be described in detail below, the at least two movement supportmembers 1016 are configured to support the seat pan member 1012 in thefloating or suspended manner from either above or below the seat panmember 1012. For example, the at least two movement support members 1016may be configured to act as a suspension assembly to support the seatpan member 1012 (from above the seat pan member 1012) in a suspendedmanner for movement with respect to the movement support frame 1014 inat least two degrees of freedom. The at least two movement supportmembers 1016 may also be configured as rigid, articulated bodies tosupport the seat pan member 1012 (from below the seat pan member 1012)in a floating manner for dynamic movement with respect to the movementsupport frame 1014 in at least two degrees of freedom.

The term “floating,” as used herein, means that the seat pan member 1012moves during normal use of the chair 1000 with the user's bodypositioned on the seat pan member 1012. Floating excludes temporarysituations where the user is moving between fixed, static positions inthe prior art adjustable chairs.

In one embodiment, the movement support frame 1014 may be made of analuminum material. In one embodiment, the movement support frame 1014may be made of A356-T6 aluminum material. In one embodiment, themovement support frame 1014 may be made of ADC12 aluminum alloymaterial. In one embodiment, the movement support frame 1014 may includeribbed structure to provide adequate strength to the movement supportframe 1014 and create an interesting visual effect. The ribbed structureof the movement support frame 1014 may optionally be covered using anopaque insert or a transparent insert.

In one embodiment, at least a portion of the movement support frame 1014may extend parallel to (and spaced apart from) the seat pan member 1012above and below the seat pan member 1012. In one embodiment, at least aportion of the movement support frame 1014 may extend parallel to (andspaced apart from) the seat pan member 1012 below the seat pan member1012.

In one embodiment, the movement support frame 1014 includes a pair ofarmrest members 1040 for supporting the arms of the user seated on thechair 1000. In one embodiment, the movement support frame 1014 includesa seat back member 1020 for supporting the back of the user seated onthe chair 1000. In another embodiment, the seat back member 1020 isoptional and the movement support frame 1014 only includes the pair ofarmrest members 1040. In one embodiment, the configuration and operationof the seat back member 1020 and the armrest members 1040 are similar tothose of the seat back member 20 and the armrest members 40,respectively as described in detail with respect to FIGS. 1-37, andhence will not be described in detail here.

FIGS. 44 and 45 show front and rear elevational views of the seat backmember 1020 of the chair 1000. The seat back member 1020 may beconnected to the movement support frame 1014 at connection portions 1147via any attachment mechanism as appreciated by one skilled in the art. Alumbar support member (e.g., similar to the lumbar support member 22 inFIGS. 1-37) of the chair 1000 may be connected to the seat back member1020 at connection portions 1149 via any attachment mechanism asappreciated by one skilled in the art. In one embodiment, the chair 1000may include additional or other connection portions to facilitate theconnection of the lumbar support member to the seat back member 1020. Aheadrest (e.g., similar to the headrest 38 in FIGS. 1-37) may beconnected to the seat back member 1020 at connection portions 1151 viaany attachment mechanism as appreciated by one skilled in the art.

The seat back member 1020 may include a mesh that is attached to itsmesh ring member. The mesh ring member may be then secured to the mainframe member of the seat back member 1020. The mesh ring member may betilted on the top of the chair 1000. The bottom of the mesh ring membermay snap over the area 1153 (e.g., where movement support members 1016may be inserted). The mesh ring member may be connected to the seat backmember 1020 at connection portions 1155 via any attachment mechanism asappreciated by one skilled in the art. In one embodiment, the mesh ringmember is optional. In other embodiments, the number of connectionportions 1147, 1149, 1151, and 1155 on the seat back member 1020 mayvary.

In one embodiment, the armrest members 1040 may be made of the samematerial as the movement support frame 1014. In one embodiment, thearmrest members 1040 may be made from aluminum material and may includerubber bumper portions at the end portions (i.e., portions pointing awayfrom the movement support frame 1014) of the armrest members 1040 toprotect the aluminum armrest members 1040.

In one embodiment, the chair 1000 may include adjustable armrest members1040 as shown and described with respect to FIGS. 57-63. An armrestportion 1040 a of the armrest member 1040 is configured to be adjustableor moveable between a raised/an elevated position as shown in FIG. 57and a lowered position as shown in FIG. 59. In one embodiment, thearmrest portion 1040 a of the armrest member 1040 may also include oneor more intermediate positions, as shown in FIG. 58, that are betweenthe raised position and the lowered position of the armrest portion 1040a.

The armrest member 1040 may include an adjustment mechanism 1123 to movethe armrest portion 1040 a between the raised/elevated position and thelowered position. The adjustment mechanism 1123 may include a simplehinge mechanism. When the armrest portion 1040 a of the armrest member1040 hinges, the armrest portion 1040 a is lifted up (e.g., in thedirection of an arrow H as shown in FIGS. 60 and 57) and moved backwards(e.g., in the direction of an arrow G as shown in FIGS. 60 and 57). Thatis, the armrest portion 1040 a is lifted upwardly and backwardlycompared to its lowered position. This configuration helps prevent thearmrest portion 1040 a from interfering with, for example, a desk.

Referring to FIGS. 60 and 61, the adjustment mechanism 1123 includes aspring loaded lock member 1125 and a lock member engaging portion 1127.The adjustment mechanism 1123 also includes linkage members 1129 thatare hingedly connected to the armrest member 1040 using connectors orpins 1131 at one end portion 1133 and are connected to the armrestportion 1040 a using connectors or pins 1137 at the other end portion1135.

The lock member 1125 may be a dowel or pin member and may be disposed onthe armrest member 1040. The lock member engaging portion 1127 mayinclude a slot 1139 having one or more openings/holes 1141. The lockmember engaging portion 1127 may be disposed on a bracket member 1143that is connected to the armrest portion 1040 a. In the illustratedembodiment, the lock member engaging portion 1127 includes slot 1139with three holes 1141. The spring loaded lock member 1125 is configuredto be located inside one of the holes 1141 of the slot 1139. Thisengagement acts as a locking mechanism to selectively retain the armrestportion 1040 a in its lowered, intermediate or raised positions. Thelocations of the three holes 1141 provide the armrest portion 1040 aheights of 0 inches (e.g., lowered position), 1 inch (e.g., intermediateposition) and 2 inches (e.g., raised position). In one embodiment, thenumber of holes/openings in the slot may vary to provide two or moreintermediate positions for the armrest portion 1040 a.

The adjustment mechanism 1123 may include a manually engageable actuator(e.g., push button) that is configured to push or move the spring loadedlock member 1125 out of the engaged hole 1141. Once the spring loadedlock member or dowel 1125 moved out of the engaged hole 1141, thearmrest portion 1040 a is free to move between the raised and thelowered positions. The manually engageable actuator (e.g., push button)may be disposed near the back portion of the armrest member 1040 so thatthere is no accidental adjustment of the armrest portion 1040 a whilethe user is getting in or out of the chair 1000.

The adjustment mechanism 1123 may also include a spring loaded ballbearing 1145 that is disposed in a pocket near the spring loaded lockmember 1125. This spring loaded ball bearing 1145 is configured tocreate friction in the armrest portion 1040 a, which provides a premiumfeel and location identification. The small holes located in line withthe spring loaded ball bearing 1145 allow a click feeling when passingover them. This configuration allows the user to know that they are inone of the three positions (i.e., lowered, intermediate, and raisedpositions) and to release the push button.

FIGS. 62 and 63 show an adjustment mechanism 1123′ for the armrestmember 1040 in accordance with another embodiment of the present patentapplication. For example, each armrest member 1040 may include amanually operated actuator 1117 and a threaded rod 1119. The manuallyoperated actuator 1117 may be a rotating dial or nut 1117 that may bemanually operated by the user seated in the chair 1000. In oneembodiment, the armrest member 1040 may include a cutout region or anopening 1121 to provide access to the rotating dial or nut 1117. Therotating dial or nut 1117 may have a knurled surface configuration. Thethreaded rod 1119 is centrally disposed with respect to the rotatingdial or nut 1117 such that the internal threads of the rotating dial ornut 1117 engage with the external threads of the threaded rod 1119.

The manually operated actuator 1117 is configured to advance thethreaded rod 1119. That is, the rotation of the manually operatedactuator 1117 in one direction advances the threaded rod 1119. Thethreaded rod 1119 may advance from left to right in the direction of anarrow F. The threaded rod 1119 is configured to be operatively connectedto the armrest portion 1040 a such that the advancement of the threadedrod 1119, in turn, raises the armrest portion 1040 a of the armrestmember 1040 both upwardly and rearwardly compared to its loweredposition. FIG. 62 shows the armrest portion 1040 a in its raisedposition. By rotating the manually operated actuator 1117 in the otherdirection, the user may cause the threaded rod 1119 to be translated ina direction opposite to that of the arrow F to move the armrest portion1040 a to its lowered position.

FIGS. 57-59 show the armrest portion 1040 a being adjusted between itslowered position and its raised position using the adjustment mechanism1123′ of the FIGS. 62 and 63. In another embodiment, the armrest portion1040 a may be adjusted between its lowered and raised positions usingthe adjustment mechanism 1123 of the FIGS. 60 and 61.

In one embodiment, the chair 1000 includes the lumbar support member forsupporting the lumbar region of the user seated on the chair 1000. Inone embodiment, the configuration and operation of the lumbar supportmember are similar to those of the lumbar support member 22 as describedin detail with respect to FIGS. 1-37 of the present patent application,and hence will not be described in detail here.

In one embodiment, the lumbar support member may be integrally formedwith or connected to the movement support frame 1014. In anotherembodiment, the lumbar support member may be integrally formed with orconnected to the seat back member 1020. In yet another embodiment, thelumbar support member is operatively connected to the seat pan member1012 and is configured to move along with the seat pan member 1012 withrespect to the movement support frame 1014 in the at least two degreesof freedom. The lumbar support member may be integrally formed with orconnected to the seat pan member 1012 such that it is configured to movealong with the seat pan member 1012 with respect to the movement supportframe 1014 in the at least two degrees of freedom.

In yet another embodiment, the lumbar support member may be configuredto be a multi-position advancing lumbar support member similar to thatdescribed in FIGS. 11-18. For example, the actuation of this moveablelumbar support member may be performed manually, semi-automatically orfully-automatically. The movement of the lumbar support member withrespect to the seat pan member 1012 and the seat back member 1020,between the first position and the second position (as described indetail with respect to FIGS. 11-18), allows for at least two distinctdivisions of the seat pan member 1012. These two divisions of the seatpan member 1012 allow the user to sit comfortably in multiple positionswith multiple areas of ergonomic support as desired by the user fortheir particular purpose(s).

In the present patent application, the term “seat base member” isinterchangeably used with the term “seat pan member,” they both refer toa member of the chair that is configured to support the weight of theuser seated in the chair and support thighs and bottom of the user whileseated in the chair. In one embodiment, the seat pan member 1012 may bereferred to as a multidirectional moveable seat pan member that isconfigured to move in at least four directions—a forward direction, arearward direction, a left side direction, and a right side direction.The seat pan member 1012 includes a generally horizontal planar memberhaving a generally horizontal rigid frame.

In one embodiment, the seat pan member 1012 is made of BASF Petra® 130FR PET (Polyethylene Terephthalate) material. This material is a 30%glass fiber reinforced, flame retardant injection molding compound basedon recycled PET (Polyethylene Terephthalate) feedstocks. In anotherembodiment, the seat pan member 1012 may be made of an appropriateplastic or other composite material having suitable strength. In oneembodiment, the seat pan member 1012 is constructed and designed tosupport a 350 pounds user perched (or leaning) on the front portion ofthe chair 1000.

FIGS. 40 and 41 shows an exploded view and an assembled view,respectively of the seat pan member 1012 of the chair 1000. The seat panmember 1012 includes a main frame member 1002, a rear frame member 1004,a cushion support member 1003, frame insert members 1005, a cushion1007, a mesh ring member 1001, mesh 1008 (as shown in FIG. 38), and sidecaps 1006.

In one embodiment, the cushion support member 1003 and both frame insertmembers 1005 are attached to the main frame member 1002. The cushion1007 is placed onto the cushion support member 1003. The mesh 1008 isattached to the mesh ring member 1001. In one embodiment, the mesh ringmember 1001 is attached using a toe-in fit arrangement under the frontedge of the cushion support member 1003. The mesh ring member 1001 isthen secured to the main frame member 1002 on the back and sides thereofusing screws or other fasteners.

In one embodiment, the front curvature of the seat pan member 1012 isconstructed and arranged to relieve pressure at the thighs of the userseated on the chair 1000. In one embodiment, the configuration of theseat pan member 1012 may be similar to that of the seat base member 12as described in detail with respect to FIGS. 1-37 of the present patentapplication. Referring to FIGS. 41-43, end portions of the movementsupport members 1016 are connected to the portions of the seat panmember 1012 to facilitate the floating movement of the seat pan member1012 with respect to the movement support frame in at least two degreesof freedom. This configuration is described in detail in discussionsbelow.

In one embodiment, the seat pan member 1012 and the seat back member1020 may have simple padded material, contoured padded material orengineered (contour forming) breathable mesh material to further providecomfort and support to the user.

In one embodiment, the mesh material may be attached to the seat panmember 1012 or the seat back member 1020 via staples or other fasteners.In another embodiment, the mesh material may be attached to the seat panmember 1012 or the seat back member 1020 by adhesive bonding or sewing.In yet another embodiment, the mesh material may be attached to the seatpan member 1012 or the seat back member 1020 via an over-molded framedesign in which edge portions of the mesh material are molded into thematerial of the seat pan member frame or the seat back member frame.

In one embodiment, the mesh material may be an elastomeric material. Inanother embodiment, the mesh material may be a polyester elastomericmonofilament material, for example, manufactured by The Quantum Group,Inc. In yet another embodiment, the mesh material may be an elastomericfabric material. In one embodiment, the mesh material may be configuredto yield excellent load-bearing properties and resiliency.

In one embodiment, the at least two movement support members 1016 areconstructed and positioned (i.e., located within the constraints) todeliver a controlled free floating movement to the seat pan member 1012.This controlled free floating movement to the seat pan member 1012 isprovided in an almost horizontal plane, i.e., the horizontal seatingplane.

In one embodiment, the at least two movement support members 1016 mayalso be referred to as a multidirectional movement assembly. Thismultidirectional movement assembly is operatively connected to the seatpan member 1012 in a manner to provide a floating movement of the seatpan member 1012 in at least two degrees movement in a generallyhorizontal plane to the movement assembly support frame 1014. In oneembodiment, the movement of the seat pan member 1012 is independent fromthe movement created by a simple seat pan swivel (provided by a pivotmechanism of the chair) or the use of casters.

In one embodiment, the at least two movement support members 1016 areconfigured to provide a floating movement to the seat pan member 1012 ofabout 2 inches in every direction (i.e., a forward direction on theX-axis, a backward direction on the X-axis, a left side direction on theY-axis, and a right side direction on the Y-axis of the seat pan member1012). In another embodiment, the at least two movement support members1016 are configured to provide a floating movement to the seat panmember 1012 of less than 2 inches in every direction (i.e., a forwarddirection, a backward direction, a left side direction, and a right sidedirection of the seat pan member 1012). In yet another embodiment, theat least two movement support members 1016 are configured to provide afloating movement to the seat pan member 1012 of more than 2 inches inevery direction (i.e., a forward direction, a backward direction, a leftside direction, and a right side direction of the seat pan member 1012).In yet another embodiment, the at least two movement support members1016 are configured to provide a floating movement to the seat panmember 1012 in every direction of up to 5, 10, 15 or 20 percent greaterthan or up to 5, 10, 15 or 20 percent less than those values describedabove.

The movement on the X and Y axes may also realize pivoting movementabout the vertical Z-axis as well. The permitted free or dynamicmovement of the seat pan member 1012 desirably allows the user tonaturally shift his/her body while remaining fully supported because theseat pan member 1012 moves with his/her body dynamically during themovements. This is an enhancement over a static design, which even ifconsidered ergonomic simply encourages the user to remain static, orshift around the static seat pan member to a sub-optimal position.

In one embodiment, each of the at least two movement support members1016 is connected to a portion of the movement support frame 1014 thatis disposed below the head height of the user seated on the chair 1000.In one embodiment, the portion of the movement support frame 1014 isdisposed above the seat pan member 1012. In one embodiment, each of theat least two movement support members 1016 is connected to one of thepair of armrest members 1040.

In one embodiment, each of the at least two movement support members1016 includes a rigid movement support member having two opposite endportions. One end portion of the rigid movement support member isconfigured to be connected to the seat pan member 1012 using amultidirectional connector and the other end portion of the rigidmovement support member is configured to be connected to the movementsupport frame 1014 using a multidirectional connector.

For example, as shown in FIG. 67 (a), the rigid movement support member1016 may be a rod member 1016 with ball joint connectors 1016 c at eachof its end portions. The rigid movement support member 1016 may be rodmember 1016 with flexible joint connectors 1016 c at each of its endportions. Referring to FIG. 67 (b), the rigid movement support member1016 may be rod member 1016 with bi-directional joint connectors 1016 cat each of its end portions. Each of the movement support member 1016 isdesigned to have at least two omni-directional connectors (i.e., one ateach of its end portions).

In one embodiment, the chair 1000 may have at least an assembly 1016 aof two movement support members 1016 with four bi-directional connectors1016 c to create a single multidirectional movement support member. Forexample, as shown in FIGS. 67 (d) and 67 (e), the assembly 1016 a of twomovement support members 1016 with four bi-directional connectors 1016 callows the movement of the seat pan member be relatively level when theseat pan member is supported by the assembly 1016 a from either above orbelow the seat pan member.

In the illustrated embodiment, four flexible movement support members1016 are shown. It is contemplated that, in other embodiment, the chair1000 may include two or three flexible movement support members 1016. Inone embodiment, each of the at least two movement support members 1016includes a flexible movement support member having two opposite endportions. One end portion of the flexible movement support member 1016is configured to be connected to the seat pan member 1012 and the otherend portion of the flexible movement support member 1016 is configuredto be connected to the movement support frame 1014.

In one embodiment, the flexible movement support member 1016 includes abraided cable or wire. In one embodiment, the flexible movement supportmember 1016 includes a flexible cord or cable as shown in FIG. 67 (c).In one embodiment, the flexible movement support member 1016 may be aflexible, weather-resistant coated Stainless Steel wire ropemanufactured by McMaster-Carr (e.g., model no: 8912T344). In oneembodiment, the flexible movement support member 1016 may have a 3/32″diameter with ⅛″ outer diameter. In one embodiment, the flexiblemovement support member 1016 may have a 7×7 construction to make itflexible. In one embodiment, the flexible movement support member 1016may have a vinyl coating that protects the wire rope from abrasion andresists UV rays. In one embodiment, the flexible movement support member1016 may be made of 18-8 stainless steel, which has good corrosionresistance. This prevents it from unraveling when cut. In oneembodiment, the flexible movement support member 1016 may be lubricatedto reduce wear. In another embodiment, the flexible movement supportmember 1016 may be an ultra-flexible lubricated cable manufactured byMcMaster-Carr. This flexible movement support member may have a 7×19construction that offers the most flexibility.

In one embodiment, the flexible movement support member 1016 includes acable having a rigid cover or covering. The flexible movement supportmember cover may include a braided metal with a co-extruded plastic overit. This cover is slipped over the flexible movement support member1016. In one embodiment, Thermoplastic Polyurethane (TPU) fittings areused at the ends of the flexible movement support member cover. In oneembodiment, crimp stop sleeves may be used at the ends of the flexiblemovement support members 1016. In one embodiment, the crimp stop sleevesmay be the crimp stop sleeves manufactured by McMaster-Carr (e.g., modelno: 3914T3).

In one embodiment, as shown in FIGS. 38 and 41, the chair 1000 includestwo rear flexible movement support members 1016 r in the rear portion ofthe chair 1000 and two front flexible movement support members 1016 f inthe front portion of the chair 1000. In one embodiment, one end portionsof the rear flexible movement support members 1016 r are configured torun through the rear frame member 1004 of the seat pan member 1012 andthrough the slots into the receptacles on the main frame member 1002 ofthe seat pan member 1012 connecting the flexible movement supportmembers to the seat pan member 1012. The rear frame member 1004 (i.e.,along with the rear flexible movement support members 1016 r through it)is then attached to the main frame member 1002 of the seat pan member1012.

In one embodiment, the other end portions of the rear flexible movementsupport members 1016 r are configured to be connected to the seat backmember 1020. For example, the other end portions of the rear flexiblemovement support members 1016 r are configured to be inserted intoopenings 1157 (as shown in FIG. 45) of the seat back member 1020 and therear flexible movement support members 1016 r (inserted in the openings1157) may be encapsulated by the mesh ring member of the seat backmember 1020. In another embodiment, the other end portions of the rearflexible movement support members 1016 r are configured to be connectedto the movement support frame 1014. In yet another embodiment, the otherend portions of the rear flexible movement support members 1016 r areconfigured to be connected to the armrest members 1040.

In one embodiment, one end portions of the front flexible movementsupport members 1016 f are configured to be fed through the holes in thefront bottom corners of the main frame member 1002 of the seat panmember 1012 connecting the flexible movement support members to the seatpan member 1012. The side caps 1006 are then installed onto the mainframe member 1002 of the seat pan member 1012.

In one embodiment, the other end portions of the front flexible movementsupport members 1016 f are configured to be connected to the movementsupport frame 1014. In another embodiment, the other end portions of thefront flexible movement support members 1016 f are configured to beconnected to the armrest members 1040.

In one embodiment, the rear movement support members 1016 r may haverigid configuration. This configuration prevents the back of the seatpan member 1012 from lifting when t user sits on the very front edge ofthe seat pan member 1012. In one embodiment, some clearance may beprovided between the frames and the ends of the flexible movementsupport member cover/Thermoplastic polyurethane (TPU) inserts, so thatthe movement of the seat pan member 1012 is not restricted.

In one embodiment, referring to FIGS. 46-53 a, the chair 1000 includes amovement limiter assembly 1075 that is operatively connected to the seatpan member 1012 and the movement support frame 1014. The movementlimiter assembly 1075 is configured to limit the range of the movementof the seat pan member 1012 with respect to the movement support frame1014 in at least one degree of freedom. In one embodiment, the movementlimiter assembly 1075 may be in the form of a lock (e.g., a lock with atoggle engagement) or a dampener that is configured to limit the rangeof the movement of the seat pan member 1012 with respect to the movementsupport frame 1014 in at least one degree of freedom. In one embodiment,the movement limiter assembly 1075 may be configured to be adjusted tolimit the movement of the seat pan member 1012 with respect to themovement support frame 1014 in any direction chosen by a user.

In the present patent application, the term “movement limiter assembly”is interchangeably used with the term “seat pan lock assembly,” theyboth refer to a member of the chair that is configured to limit therange of the movement of the seat pan member with respect to themovement support frame in at least one degree of freedom, bias the seatbase member to the center (or a center position), or restrict or dampenthe movement of the seat base member.

The movement limiter assembly 1075 is configured to be moveable betweena locked or an engaged position as shown in FIGS. 47, 49, and 51 and anunlocked or a disengaged position as shown in FIGS. 46, 48, and 50. Theseat pan member 1012 is permitted to be moved with respect to themovement support frame 1014 when the movement limiter assembly 1075 isin the unlocked or disengaged position. The seat pan member 1012 isprevented from moving with respect to the movement support frame 1014when the movement limiter assembly 1075 is in the locked or engagedposition.

In one embodiment, as will be explained below with respect to FIGS.46-53 a, the movement limiter assembly 1075 is moveably or pivotablyconnected to the movement support frame 1014 and is configured to engagewith a portion of the seat pan member 1012 to limit the range of themovement of the seat pan member 1012 with respect to the movementsupport frame 1014 in at least one degree of freedom. It is alsocontemplated that, in another embodiment of the present patentapplication, the movement limiter assembly 1075 may be moveably orpivotably connected to the seat pan member 1012 and may be configured toengage with a portion of the movement support frame 1014 to limit therange of the movement of the seat pan member 1012 with respect to themovement support frame 1014 in at least one degree of freedom.

Referring to FIGS. 52 and 53, the movement limiter assembly 1075 mayinclude a housing 1077, lock assembly 1079 connected to the housing 1077and spring(s) 1081 (as shown in FIG. 53a ) disposed in the housing 1077.In one embodiment, the housing 1077 is configured to be mounted with thealuminum frame of the movement support frame 1014 so as to be hiddenfrom view.

In one embodiment, the lock member 1079 may include U-shaped channel(s)1093 that are configured to provide strength to the lock member 1079. Inone embodiment, the lock assembly 1079 may include two lock members 1095that are spaced apart and connected to each other using cross bracing1095 c. The cross bracing 1095 c is configured to provide rigidity tothe lock assembly 1079.

In one embodiment, the lock assembly 1079 is pivotably connected to thehousing 1077. For example, a pin or other similar member is configuredto pass through openings 1107 of the lock assembly 1079 and opening 1109of the housing 1077 to pivotably connect the lock assembly 1079 to thehousing 1077. The lock assembly 1079 is also connected to portions 1105of the housing 1077 via the springs 1081.

Each lock member 1095, at its free end, includes a lock element 1097that is constructed and arranged to engage with a lock element engagingportion 1099 disposed on the seat pan member 2012. In one embodiment,the lock element 1097 is in the form of a pin 1097 that is constructedand arranged to engage with a pin receiving opening 1099 disposed on theseat pan member 2012. For example, the pins 1097 may have taperedconfiguration so as to easily engage with their corresponding pinreceiving openings 1099 disposed in the seat pan member 2012. In anotherembodiment, the lock element may be in the form of an opening that isconstructed and arranged to receive a pin disposed on the seat panmember 2012. In yet another embodiment, the lock element and the lockelement engaging portion may include any other shapes and configurationsas would be appreciated by one skilled in the art.

In one embodiment, the lock assembly 1079 may include guiding members(or ribs) 1101 that are configured to guide the lock element 1097 andprevent the lock element 1097 from getting stuck behind or in front ofthe seat pan member 2012 while engaging with the corresponding pinreceiving opening 1099.

In one embodiment, the lock assembly 1079 is spring-loaded/spring-biasedsuch that it is configured to auto-engage once the lock assembly 1079 isreleased. In one embodiment, this configuration of the lock assembly1079 only requires the user to move until the lock elements 1097 findtheir corresponding lock element engaging portions 1099. The springs1081 are configured to force or bias the arm members 1095 to pivotupwards. The springs may also have other configurations.

In one embodiment, the movement limiter assembly 1075 may includeengagement portions that are configured to hold the lock assembly 1079in its disengaged or unlocked position. In one embodiment, the lockassembly 1079 is configured to lock out of the way when it is not inuse. This configuration of the lock assembly 1079 enables the lockassembly 1079 not to interfere with normal movement of the seat panmember 2012. In one embodiment, the hinge point HP is almost level withthe movement of the seat pan member 2012, so that lock elements 1097engage well with their corresponding lock element engaging portions 1099even if level of the seat pan member 2012 varies.

Referring to FIGS. 50 and 51, the movement limiter assembly 1075 mayinclude manually engageable portion(s) 1103 that are configured to beengageable by the user to move the movement limiter assembly 1075between the locked or engaged position and the unlocked or disengagedposition. The manually engageable portion(s) 1103 may be operativelyconnected to the movement limiter assembly 1075.

The manually engageable portion(s) 1103 are constructed and arranged sothat they do not interfere with the floating movement of the seat panmember 1012. For example, as shown in FIG. 50, the manually engageableportion(s) 1103 release pop up when the movement limiter assembly 1075is in the unlocked or disengaged position. As shown in FIG. 51, themanually engageable portion(s) 1103 move down (and out of the way) whenthe movement limiter assembly 1075 is in the locked or engaged position(i.e., the lock member 1097 of the lock member 1079 is engaged with thelock element engaging portions 1099).

In another embodiment, the manually engageable portion(s) 1103 areoptional and the user may move the movement limiter assembly 1075between the locked or engaged position and the unlocked or disengagedposition by simply pulling the lock member 1079. In another embodiment,the movement limiter assembly 1075 may have configuration and operationsimilar to those of the seat base member locking mechanism 902 of FIGS.10Q and 10R.

In one embodiment, the chair 1000 may include a built-in movementlimiter assembly that is disposed on a portion of the movement supportmember frame 1014 or the seat pan member 1012. In another embodiment,the chair 1000 may include a retrofitted movement limiter assembly thatis attached to the chair 1000 by the user later on. In one embodiment,the movement limiter assembly may include a bolt-on feature.

The movement limiter assembly 1075 may include a mounting plate 1083that is configured to mount the movement limiter assembly 1075 to themovement support frame 1014. The housing 1077 may be connected to themounting plate 1083 using a toe-in tab 1091 or any other connectorarrangement. The housing 1077 may be locked to the mounting plate 1083using thumb screws or any other lock arrangement. For example, the thumbscrews are configured to pass through an opening 1085 of the housing1077 and an opening 1087 of the mounting plate 1083 to lock the housing1077 to the mounting plate 1083. In one embodiment, fasteners areconfigured to pass through openings 1089 a of the mounting plate 1083and openings 1089 b of the movement support frame 1014 to lock themounting plate 1083 to the movement support frame 1014. In oneembodiment, the mounting plate 1083 is optional and the housing 1077 maybe configured to be directly connected to the movement support frame1014. In one embodiment, the movement limiter assembly 1075 pivotsaround the mounting point. In some instances, some pivoting motion ofthe movement limiter assembly 1075 may be desirable, even when themovement limiter assembly 1075 is in its locked position.

In one embodiment, as shown in FIG. 56, the toe-in tab 1091 may bewidened so that the movement limiter assembly 1075 cannot flex or pullaway from the mounting plate 1083. In another embodiment, use on tab ateach corner of the movement limiter assembly 1075 may be used so thatthe movement limiter assembly 1075 cannot flex or pull away from themounting plate 1083. These configurations provide more rigidity to themovement limiter assembly 1075.

In one embodiment, mounting locations (e.g., the openings 1089 a of themounting plate 1083) are moved to corners of the movement limiterassembly 1075. The wider mounting locations may be covered withremovable Thermoplastic polyurethane (TPU) sections so that the mountinglocations are hidden when the movement limiter assembly 1075 is notused.

In one embodiment, as shown in FIG. 55, bosses 1111 may be added to thealuminum chair frame 1014. The bosses 1111 may be nested between theribs of the aluminum chair frame 1014 and can be covered by theThermoplastic polyurethane (TPU) insert when not in use. The housing1077 of the movement limiter assembly 1075 may be extended to engagewith the bosses 1111 disposed on the aluminum chair frame 1014. Thisconfiguration eliminates the mounting plate 1083 that is provided forattachment of the housing 1077 to the movement support frame 1014 andoffers complete locking of the pivoting motion of the movement limiterassembly 1075.

In one embodiment, the user may be manually push or pull the lockassembly 1079 to actuate or operate the movement limiter assembly 1075.In another embodiment, as shown in FIG. 54, an actuation handle 1113 maybe added to a side of the movement limiter assembly 1075 to actuate oroperate the movement limiter assembly 1075. The actuation handle 1113may extend outwardly from the side of the movement limiter assembly 1075for easier access and use of the movement limiter assembly 1075.

In one embodiment, glass-filled-nylon material or metal materialsub-structure may be used to provide strength and rigidity, especiallyat the mounting points of the movement limiter assembly 1075.

In one embodiment, the seat pan lock or the movement limiter assembly isconfigured to only engage when manually activated. In anotherembodiment, the movement limiter assembly may be configured to be moredynamic in nature. The dynamic configuration of the movement limiterassembly may be due to the movement limiter assembly can be sprung orthe movement limiter assembly can have an elastomeric property (i.e.,slightly stretch with more force). Such a movement limiter assembly isconfigured to be engaged constantly to regulate the movement of the seatpan member.

The chair 1000 also includes an actuator that is configured to operatethe least two movement support members 1016 for providing the movementof the seat pan member 1012 with respect to the movement support frame1014 in the at least two degrees of freedom. In one embodiment, theconfiguration and operation of the actuator are similar to those of theactuator 18 as described in detail with respect to FIGS. 1-37 of thepresent patent application, and hence will not be described in detailhere. Also, the interaction of the actuator and the at least twomovement support members 1016 of the chair 1000 is similar to that ofthe actuator 18 and the suspension assembly 16 described with respect toFIGS. 1-37, and hence will not be described in detail here. For example,in one embodiment, the actuator may be configured to operate a drivesystem to adjust the length (e.g., lengthen or shorten) of the least twomovement support members 1016.

Based on the distance between the pivot point (i.e., the point at whichthe seat pan member of the chair pivots) and the axis of the chair's gasspring, there are two types of stock/pivot mechanisms—a standard pivotmechanism and a knee tilt pivot mechanism. The standard (prior art)pivot mechanism is shown in FIG. 64 and the knee tilt pivot mechanismused in the present patent application is shown in FIG. 65. In thepresent patent application, the main tilt mechanism in which the gasshock and the movement support member frame attach to, is called theknee tilt mechanism because the chair bends downward from where theuser's knees bend when the user is sitting in the chair. By contrast,the front of the user's knee moves upwards as the seat back member ofthe standard pivot mechanism chair pivots backwards to the reclineposition.

As shown in FIGS. 64 and 65, the pivot point P_(KT) of the knee tiltmechanism is much further forward than the pivot point of the standardmechanism P_(S). The recliner effect also varies between the knee tiltpivot mechanism and the standard pivot mechanism. For example, when theuser reclines on the chair with the standard pivot mechanism, the user'slegs raise and their torso lowers. With the knee tilt pivot mechanism,the user's legs do not raise and the torso drops (i.e., essentially theuser is pivoting from their knee). This also pulls the users seat panmember backwards against the lumbar in the mesh and is quite comfortableand supportive. The knee tilt configuration is advantageous (thismovement is also captured, for example, in FIG. 6A) since the seat panmember moves the user against the seat back member of the chair withmore of your weight naturally resting on the back lumbar region of thechair than other chairs where the seat pan member does not movebackwards in a free motion state as the present patent application.

FIG. 66 shows an adjustment control for the stock/pivot mechanism of thechair 1000. In one embodiment, the chair 1000 includes a singleadjustment control member 1115 that is configured to control the reclinespring, to operate the recline lock, to adjust the height of themovement support frame 1014 (and, therefore, the seat pan member 1012)and/or to control/operate other features or components of thestock/pivot mechanism of the chair 1000. The single adjustment controlmember 1115 is configured to be manually engageable by the user.

For example, the single adjustment control member 1115 is configured tobe pulled outwardly, in the direction of an arrow A, to engage therecline lock and to be pushed in, in the direction of an arrow B, torelease the recline lock. The same single adjustment control member 1115is configured to be twisted in the direction of the arrow C (or theclockwise direction) to adjust the height of the movement support frame1014 (and, therefore, the seat pan member 1012). Also, the singleadjustment control member 1115 is configured to be rotated to adjust thetightness of the recline spring. For example, the single adjustmentcontrol member 1115 is configured to be rotated in the direction of thearrow D (or the clockwise direction) to increase the tightness of therecline spring and to be rotated in the direction opposite to that ofthe arrow D (or the counter clockwise direction) to decrease thetightness (i.e., loosen) of the recline spring. The structure andoperation of the recline lock, the recline spring, and the heightadjustment mechanism of the chair are generally known to one skilled inthe art and hence will not described in detail here.

The foregoing illustrated embodiments have been provided to illustratethe structural and functional principles of the present patentdisclosure and are not intended to be limiting. To the contrary, thepresent patent disclosure is intended to encompass all modifications,alterations and substitutions within the spirit and scope of theappended claims.

What is claimed is:
 1. A chair comprising: a seat pan member; a movementsupport frame; and a plurality of movement support members operativelyconnected to the seat pan member and the movement support frame, whereinthe plurality of movement support members are essentially inextensibleand configured to support and guide the seat pan member in a controlledfloating manner for dynamic movement with respect to the movementsupport frame in at least two degrees of freedom of the seat pan member,the at least two degrees of freedom being parallel to a horizontalseating plane, wherein the plurality of movement support memberscomprise a plurality of forwardly disposed movement support members anda rearwardly disposed movement support member, at least the rearwardlydisposed movement support member having a flexible member having twoopposite end portions, wherein one end portion of the flexible member isconnected to the seat pan member and the other end portion is connectedto the movement support frame, the rearwardly disposed movement supportmember further comprising a rigid covering on the flexible memberthereof configured to prevent a rear portion of the seat pan member fromlifting upwardly when a user sits on a front edge portion of the seatpan member.
 2. A chair according to claim 1, wherein the at least twodegrees of freedom of the seat pan member include two translationalmovements of the seat pan member along two mutually perpendicular axes.3. A chair according to claim 1, wherein each of the forwardly disposedmovement support members includes a flexible member having two oppositeend portions, and wherein one end portion of the flexible member isconnected to the seat pan member and the other end portion of theflexible member is connected to the movement support frame.
 4. A chairaccording to claim 3, wherein the flexible member of the rearwardlydisposed movement support member includes a cable having the rigidcovering thereon.
 5. A chair according to claim 1, wherein each of themovement support members is connected to a portion of the movementsupport frame that is disposed below the head height of the user to beseated on the chair.
 6. A chair according to claim 5, wherein theportion of the movement support frame is disposed above the seat panmember.
 7. A chair according to claim 1, wherein the movement supportframe includes a pair of armrest members, and wherein each of themovement support members is connected to one of the pair of armrestmembers.
 8. A chair according to claim 1, wherein the movement supportframe comprises a seat back member attached separately from the seat panmember for supporting the back of the user to be seated on the chair. 9.A chair according to claim 1, further comprising a movement limiterassembly operatively connected to the seat pan member and the movementsupport frame, wherein the movement limiter assembly is configured tolimit the range of the movement of the seat pan member with respect tothe movement support frame in the at least two degrees of freedom of theseat pan member.
 10. A chair according to claim 1, further comprising alumbar support member for supporting the lumbar region of the user to beseated on the chair.
 11. A chair according to claim 10, wherein thelumbar support member is operatively connected to the seat pan memberand is configured to dynamically move along with the seat pan memberwith respect to the movement support frame in the at least two degreesof freedom of the seat pan member.
 12. A chair according to claim 1,wherein the at least two degrees of freedom of the seat pan memberinclude a forward and backward movement of the seat pan member, and aside to side (left to right) movement of the seat pan member.
 13. Achair according to claim 1, wherein the movement support members areconfigured to support and guide the seat pan member in the controlledfloating manner for the dynamic movement with respect to the movementsupport frame in at least three degrees of freedom of the seat panmember, and wherein the at least three degrees of freedom include twotranslational movements of the seat pan member along two mutuallyperpendicular axes parallel to the horizontal seating plane and onerotational movement of the seat pan member about an axis perpendicularto the two mutually perpendicular axes.
 14. A chair according to claim13, further comprising an adjustment actuator for adjusting movement ofthe seat pan member with respect to the movement support frame includingtwo rotational movements of the seat pan member with respect to themovement support frame about the two mutually perpendicular axes.
 15. Achair according to claim 1, further comprises an ergonomic positionsensor arrangement that is configured to sense the position of the userto be seated on the seat pan member for outputting data to determine howthe user is sitting in comparison to a predetermined target sittingposition.
 16. A chair according to claim 15, wherein the ergonomicposition sensor arrangement is configured to sense the movement of theuser to be seated on the seat pan member to determine whether the useris moving correctly between various sitting positions.
 17. A chairaccording to claim 1, wherein the seat pan member includes a generallyhorizontal planar member having a generally horizontal rigid frame. 18.The chair according to claim 1, further comprising a seat back memberattached to the movement support frame.
 19. A chair comprising: a seatpan member; a movement support frame; and at least two movement supportmembers operatively connected to the seat pan member and the movementsupport frame, wherein the at least two movement support members areconfigured to support and guide the seat pan member in a controlledfloating manner for dynamic movement with respect to the movementsupport frame in at least two degrees of freedom of the seat pan member,the at least two degrees of freedom being parallel to a horizontalseating plane, and wherein each of the at least two movement supportmembers includes a rigid member having two opposite end portions, andwherein one end portion of the rigid member is configured to beconnected to the seat pan member using a multidirectional connector andthe other end portion of the rigid member is configured to be connectedto the movement support frame using a multidirectional connector. 20.The chair of claim 19, further comprising a lumbar support member forsupporting the lumbar region of a user to be seated on the chair,wherein the lumbar support member is operatively connected to the seatpan member and is configured to dynamically move along with the seat panmember with respect to the movement support frame in the at least twodegrees of freedom of the seat pan member.
 21. The chair according toclaim 20, further comprising a seat back member attached to the movementsupport frame.
 22. A chair comprising: a seat pan member; a movementsupport frame; and at least two movement support members operativelyconnected to the seat pan member and the movement support frame, whereinthe at least two movement support members are configured to support andguide the seat pan member in a controlled floating manner for dynamicmovement with respect to the movement support frame in at least twodegrees of freedom of the seat pan member, the at least two degrees offreedom being parallel to a horizontal seating plane, further comprisingan actuator configured to operate the at least two movement supportmembers for providing two rotational movements of the seat pan memberwith respect to the movement support frame, wherein the two rotationalmovements of the seat pan member are about two mutually perpendicularaxes parallel to the horizontal seating plane.
 23. The chair accordingto claim 22, further comprising a lumbar support member for supportingthe lumbar region of a user to be seated on the chair, wherein thelumbar support member is operatively connected to the seat pan memberand is configured to dynamically move along with the seat pan memberwith respect to the movement support frame in the at least two degreesof freedom of the seat pan member.
 24. A chair comprising: a seat panmember; a movement support frame; a seat back member attached to themovement support frame; and at least two movement support membersoperatively connected to the seat pan member and the movement supportframe, wherein the at least two movement support members are essentiallyinextensible and configured to support and guide the seat pan member ina controlled floating manner for dynamic movement with respect to themovement support frame and the seat back member in at least two degreesof freedom of the seat pan member, the at least two degrees of freedombeing parallel to a horizontal seating plane, wherein the at least twodegrees of freedom of the seat pan member include a forward and backwardmovement of the seat pan member, and a side to side (left to right)movement of the seat pan member, and wherein the seat pan member, duringits backward movement, is configured to extend under the seat backmember.
 25. A chair according to claim 24, wherein the movement supportmembers comprise a plurality of forwardly disposed movement supportmembers and a rearwardly disposed movement support member, and whereinat least the rearwardly disposed movement support member having aflexible member having two opposite end portions, wherein one endportion of the flexible member is connected to the seat pan member andthe other end portion is connected to the movement support frame, therearwardly disposed movement support member further comprising a rigidcovering on the flexible member thereof configured to prevent a rearportion of the seat pan member from lifting upwardly when a user sits ona front edge portion of the seat pan member.
 26. The chair according toclaim 24, further comprising a lumbar support member for supporting thelumbar region of a user to be seated on the chair, wherein the lumbarsupport member is operatively connected to the seat pan member and isconfigured to dynamically move along with the seat pan member withrespect to the movement support frame in the at least two degrees offreedom of the seat pan member.
 27. A chair comprising: a base assemblyconfigured to stably support the chair on a surface; a seat pan member;a movement support frame, the movement support frame being supported onthe base assembly; at least two movement support members configured tooperatively connect the seat pan member to the movement support frame;an actuator configured to operate the at least two movement supportmembers for providing a rotational adjustment of the seat pan memberwith respect to the movement support frame, wherein the rotationaladjustment of the seat pan member is about one of two mutuallyperpendicular axes parallel to a horizontal seating plane; and a drivesystem operatively connected to the at least two movement supportmembers and the actuator, wherein the actuator is configured to operatethe drive system to adjust the length of the least two movement supportmembers for providing the rotational adjustment of the seat pan memberwith respect to the movement support frame wherein the drive systemincludes a pulley, a spring, and a ratchet assembly.
 28. The chair ofclaim 27, wherein the at least two movement support members include afirst movement support member and a second movement support member,wherein the first movement support member and the second movementsupport member are disposed on opposing sides of the seat pan member,and wherein the actuator is configured to operate the drive system toeither maintain the length of or lengthen one of the first movementsupport member and the second movement support member and either toshorten or maintain the length of the other of the first movementsupport member and the second movement support member to move the seatpan member to a side tilt position with respect to the movement supportframe.
 29. The chair of claim 27, wherein the at least two movementsupport members include a first forward movement support member, asecond forward movement support member, a first rearward movementsupport member, and a second rearward movement support member, whereinthe first forward movement support member and the second forwardmovement support member are disposed on opposing sides of the seat panmember in a forward portion of the chair, wherein the first rearwardmovement support member and the second rearward movement support memberare disposed on the opposing sides of the seat pan member in a rearwardportion of the chair, and wherein the actuator is configured to operatethe drive system to either maintain the length of or lengthen the firstrearward movement support member and the second rearward movementsupport member and either to shorten or maintain the length of the firstforward movement support member and the second forward movement supportmember to move the seat pan member to a rearward tilt position withrespect to the movement support frame.
 30. The chair of claim 27,wherein the at least two movement support members include a firstforward movement support member, a second forward movement supportmember, a first rearward movement support member, and a second rearwardmovement support member, wherein the first forward movement supportmember and the second forward movement support member are disposed onopposing sides of the seat pan member in a forward portion of the chair,wherein the first rearward movement support member and the secondrearward movement support member are disposed on the opposing sides ofthe seat pan member in a rearward portion of the chair, and wherein theactuator is configured to operate the drive system to either maintainthe length of or lengthen the first forward movement support member andthe second forward movement support member and either shorten or tomaintain the length of the first rearward movement support member andthe second rearward movement support member to move the seat pan memberto a forward tilt position with respect to the movement support frame.31. The chair of claim 27, wherein the spring is a torsion spring thatis configured to dampen the movement of the pulley.
 32. The chair ofclaim 27, wherein the ratchet assembly is configured to lock the lengthof the at least two movement support members at a desired position untilreleased.